The all-time stolen base leader, Rickey Henderson, swipes third in 1985

In baseball statistics, stolen bases (denoted by SB) is a count of the number of bases successfully stolen by a player. In the 19th century, stolen bases were credited when a baserunner reached an extra base on a base hit from another player. For example if a runner on first base reached third base on a single, it would count as a steal. A Scottish-born outfielder named Hugh Nicol was once credited with 138 of these in one year. Modern steal rules were implemented in 1898, and steals are now only credited when a runner successfully takes an extra base while the ball is being pitched. In addition, if the situation of the game is such that the steal is of little use (usually late innings with a large difference in score), and the catcher does not attempt to throw out the runner, the runner is not credited with a steal, and the base is attributed to defensive indifference.

Rickey Henderson is the most prolific base stealer in Major League Baseball, with 1,369 over his career. That total is 431 more than second place Lou Brock and, as of the end of the 2004 season, an astonishing 824 more than the next highest active player Kenny Lofton. He also holds the modern record for steals in one season with 130 in 1982.

It is sometimes said that first base can be "stolen", because the batter becomes a runner if the catcher drops the ball after a third strike; if the batter reaches first as a result, it is recorded not as a stolen base, but as a passed ball. The last recorded instance of a player "stealing" first base during a conventional, caught pitch occurred on September 4, 1908, by Detroit's Germany Schaefer in a game against Cleveland. Schaefer was on second base and his teammate Davy Jones was on third, and in an attempt to draw a throw that would permit Jones to safely steal home Schaefer bolted for first base. Cleveland's catcher didn't fall for the trick and held the ball, allowing Schaefer to steal first base. This tactic of reverse-stealing has since been outlawed.

It is possible for a player to steal home base, often occurring during a "double steal," when a runner of first base attempts to steal second and the runner on third anticipates a throw to second base. Ty Cobb was the most prolific as such a feat, amassing the records for most steals of home in a single season with 8 as well as for a career with 54.

MLB.com list of All-Time Career steals leaders